Tamper-indicating food container lid

ABSTRACT

A tamper-indicating wide-mouth food container including a thermoformed or injection molded lid having a downwardly-extending rim portion which engages the rim of the container, the rim portion separated by a tear strip along one or more slitted peripheral lines when the container is first opened. A slitting line extends downwardly from the peripheral line from the horizontal over a small area to form a manually-engageable tab which facilitates the tearing of the stilted peripheral line. When the tear strip is separated, that part of the rim portion below the tear strip falls free of engagement to provide an indication of a first opening of the container.

Reference is made to our co pending application. Ser. No. 60/586,073filed Jul. 8, 2004, to which a claim of priority is made.

BACKGROUND OF THE INVENTION

This invention relates generally to the field of wide-mouth foodcontainers, In particular intended for the retail sale of such productsas cottage cheese, margarine, and the like. Container and lid could beround or rectangular in shape.

Attempts have been made in the prior art to provide a tamper-proofconstruction, or at least a tamper-indicating lid without the need ofcomplex molding techniques. The most commonly used process is to shrinkwrap in the area of the rim of the lid, overlying the mouth of thecontainer. The shrink-wrapping must be broken before the lid canremoved. This installation process is troublesome, and requires aseparate machine for installation. The opening of the package is alsonot usually easy, and often requires the use of a tool such as a knifeblade. As a result, the process is relatively expensive, and could besomewhat dangerous to the consumer.

SUMMARY OF THE INVENTION

Briefly stated, the invention contemplates the provision of an improvedtamper-indicating package of the type disclosed, in which the need for aseparate shrink-wrapping operation is eliminated. To this end, the lidor cover is commonly thermoformed from sheet material or injectionmolded to include a vertical skirt with a peripheral portion of thinwalled cross section to allow flexing of a part of the rim over anoutwardly-extending bead on the container. The skirt includes a tearstrip forming a manually-engageable tab. A portion of the strip belowthe skirt engages a bead on the container, and may be heat sealed ifdesired, or allowed to fall free from the container after the tear stripis separated. The container at the mouth thereof includes acorresponding flexible skirt with an outwardly flared edge to engage theskirt of the lid. The tear strip is preferably formed by using laserbeams which also form the manually-engageable tab. After a first openingof the container, it is closed in normal manner using a plug-typesealing means on the lid which engages a corresponding recess on theinner surface of the container mouth.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, to which reference will be made in the specification,similar reference characters have been employed to designatecorresponding parts throughout the several views.

FIG. 1 is a fragmentary sectional view of a lid or cover elementcomprising an embodiment of the invention.

FIG. 2 is a fragmentary sectional view of a corresponding containerelement.

FIG. 3 is perspective view of a round lid on a container with a tab

FIG. 4 is a perspective view of a complete lid with two completecircumferential slit lines with a tab

FIG. 5 is an enlarged fragmentary perspective view showing a line ofslitting to form an opening tab on a lid with two circumferential slitlines

FIG. 6 is a perspective view of a complete lid with one completecircumferential slit line with a tab

FIG. 7 is an enlarged fragmentary perspective view showing a line ofslitting to form an opening tab on a round lid

FIG. 8 is a perspective view of a rectangular lid with two completecircumferential slit lines with a tab

FIG. 9 is an enlarged fragmentary perspective view of slitting to forman opening tab on a rectangular lid

DETAILED DESCRIPTION OF THE DISCLOSED EMBODIMENT

In accordance with the invention, the device, generally Indicated byreference character 10 comprises broadly: a container element 11 and alid or cover element 12.

The container element 11 may be of known type, commonly formed byinjection molding or thermoforming. It includes a bottom wall 20, anarcuate side wall 21, an upper rim section 22, and a lid-engagingportion 23 forming upper and lower recesses 24 and 25. It also includesa radially-extending recess 26 supporting a horizontal portion 27 and abead-forming portion 28 defining an annular recess 29 engaged by the lidelement upon first installation.

The lid element 12, commonly formed as a thermoforming or injectionmolding operation, and includes a horizontal main wall 30, an inner rimmember 31, a radially-extending wall 32 and an outer rim member 33. Therim member 33 includes a single or multiple lines of slitting 34,preferably formed using a Laser beam, and as seen in FIG. 3, include anoutwardly-oriented portion to form a manually-engageable tab 35.

During an initial opening operation, the user first separates the tab 35and moves the same circumferentially to result in severing that portionof the slitted lines 34 which lie in a horizontal plane. This motionwill also separate that portion of the lid 38 located below thehorizontally-slitted lines so that it will fall away from the container.When the lid is replaced, there will be visually observable evidencethat the container was initially opened. If desired, the portion 38 maybe heat sealed in position to remain after the lid is removed.

It may thus be seen that we have invented novel and highly usefulimprovements in lid construction for wide-mouth containers in which theneed for heat shrinking additional material surrounding the rim of thelid is eliminated. The novel lid construction is commonly thermoformedor injection molded. The lower flared portion of the lid forms thelocking means which, at the time of installation, radially expands pastthe outermost mouth dimension of the container, and contracts beneaththe rim of the container to provide a locking means. By laser slittingnot only the horizontal parting lines, but forming a manually-engageabletab, those portions of the lid located below the horizontal slittingline will be ruptured at the time of opening and fall away from thecontainer, leaving clear evidence of an initial opening of thecontainer.

It is noted that after first opening, the lid is removably sealed in thecontainer mouth and maintained by engagement of members 31 and 33 withmembers 23, 26, and 28.

It may thus be seen that we have invented novel and highly usefulimprovements in a combination lid and container, in which the need for aheat shrinking operation is eliminated while providing a visualindication that the container may have been tampered with by the time itreaches the consumer. This is accomplished by providing the lid with adownwardly-extending flared member which may be stretched over a bead onthe container rim to subsequently contract when the lid is fully seated.The flared portion is provided with a tear strip which must be removedbefore the lid can be manually removed, and the removal of the tearstrip forms a gap which is readily observable. Optionally, with theprovision of vertical slitting to form a manually-engageable tab on thetear strip, the slitting may be continued into the area below the tearstrip so that it will fall away from the container at the same time.Until the tear strip has been removed, it is difficult to remove the lidfrom the container.

We wish it to be understood that we do not consider the invention to belimited to the precise details shown and described in the specification,for obvious modifications will occur to those skilled in the art towhich the invention pertains.

We claim:
 1. In a lid for a wide-mouth container including a plug-shapedcentral portion and an arcuate rim extending radially outward of saidcentral portion, the improvement comprising: an outer arcuate rimmember, and an interconnected flared portion extending downwardly fromsaid outer rim member to engage a rim of said container; said outer rimhaving at least one horizontally-oriented lines of slitting, and a lineof slitting extending downwardly over a limited arcuate area betweensaid horizontally-oriented line to form a manually engageable tab abovesaid flared portion; whereby upon the tearing of said lines of slittingusing said tab, said flared portion is disconnected from said lid topermit removal of said lid from the mouth of an engaged container, andprovide a visual indication that the container has been initiallyopened.
 2. The improvements set forth in claim 1, wherein said lid isformed commonly by thermoforming
 3. The improvement inset forth in claim1, in which the lines of slitting are performed by a laser beam
 4. Theimprovements set forth in claim 1, wherein said lid is formed commonlyby injection molding
 5. The improvement inset forth in claim 1, in whichthe lines of slitting are performed by a mechanical cutting knife
 6. Alid for a wide mouth container, said lid having a plug-shaped centralwall and an arcuate member extending radially outward of said centralwall; an interconnected flared member extending downwardly from saidarcuate member for engaging a corresponding bead at a rim of acontainer, and flanged member forming a hook-like means for engaging acorresponding rim of said container; said flanged member having at leastone horizontally-oriented parallel lines of slitting to form amanually-engageable tab above said flared member, whereby upon thetearing of said flared member employing said tab along said parallelline(s) of slitting, a gap is formed to provide visual tamper-indicatingmeans.
 7. The lid as set forth in claim 4, in combination with acorresponding container having a bead-forming portion on an edge thereofselectively engaged with said hook-like means.